This invention is concerned with remote control adjustment of electronic signal receivers and more particularly to a system for providing substantially simultaneous remote actuation of a plurality of control functions in a color television receiver.
Remote control tuning of television receivers has, in the past, been accomplished in many different ways. In one type of known system, a remote control transmitter is utilized to transmit a different ultrasonic frequency signal for actuation of each selected remote control function. Thus, where eight functions are to be controlled (e.g., volume up and down, color up and down, tint plus or minus, channel up and down), eight different frequencies in the vicinity, for example, of 30 to 40 KHz are transmitted and received in the ultrasonic remote control system. The use of a plurality of ultrasonic frequencies requires that the remote control receiver have a relatively large bandwidth. A receiver with a relatively large bandwidth is generally more susceptible to extraneous noise signals than one with a narrower bandwidth. Further, receiving and transmitting transducers having relatively broad bandwidth generally have a lower sensitivity than their narrow bandwidth counterparts, thus requiring the transmitter to expand a relatively large amount of energy to effect reliable signal reception.